Healthy environmentalism is driven by a desire to live in a beautiful environment, in peace and in harmony with nature, using earth’s resources sustainably. It wants to have a wonderful world to leave to future generations – a world where everyone has free access to clean air, water and nutritious, healthy food, where animal species are protected and where human beings can fulfil their potential. Unhealthy environmentalism is motivated by contempt for human beings, business and science, the idealisation of nature, anthropomorphism and thinly veiled pathologies of the unhealthy left. We must promote healthy environmentalism, helping it to thrive and integrate itself with science, politics and business. We must heavily suppress unhealthy environmentalism as an obstacle to our common future.